Poly(arylene sulfide ketone)s, PASK, are an important class of engineering thermoplastics. Poly(arylene sulfide ketone)s are of commercial interest for fil,m fiber, moldings and composite applications because of their high melting points. One process for producing poly(arylene sulfide ketone)s involves the reaction of a dihalobenzophenone such as a dichlorobenzophenone with an alkali metal sulfide. The alkali metal sulfide is prepared by the reaction of an alkali metal hydrosulfide with an alkali metal hydroxide using virtually precise equimolar amounts (stoichiometric amounts) of the alkali metal hydrosulfide with respect to the alkali metal hydroxide, since an excess of either component has been considered undesirable.
However, a major disadvantage with the poly(arylene sulfide ketone)s has been a relatively low molecular weight. It would be most desirable to be able to produce poly(arylene sulfide ketone)s having a relatively high molecular weight. The high molecular weight poly(arylene sulfide ketone)s would exhibit improved impact strength and toughness when compared to low molecular weight poly(arylene sulfide ketone)s.
It is an object of my invention to provide a process for preparing a high molecular weight poly(arylene sulfide ketone). It is a further object of my invention to prepare high molecular weight poly(arylene sulfide ketone)s.